The present disclosure pertains to paper laminates and more particularly to paper laminates useful as floor surfacing materials. In particular, the disclosure relates to fluorourethane treated dried overlays of laminate surfaces which have improved cleanability, oil resistance and abrasion resistance.
Paper laminates are in general well-known in the art, being suitable for a variety of uses including table and desk tops, countertops, wall panels, floor surfacing, tableware and the like. Paper laminates have such a wide variety of uses because they can be made to be extremely durable, and can be also made to resemble (both in appearance and texture) a wide variety of construction materials, including wood, stone, marble and tile, and can be decorated to carry images and colors.
Typically, the paper laminates are made from papers by impregnating the papers with resins of various kinds, assembling several layers of one or more types of laminate papers, and consolidating the assembly into a unitary core structure while converting the resin to a cured state. The type of resin and laminate paper used, and composition of the final assembly, are generally dictated by the end use of the laminate.
Decorative paper laminates can be made by utilizing a printed decorative paper layer as upper paper layer and various support paper layers in the unitary core structure. The decorative paper is typically highly opaque so that the appearance of the support layers below the decorative paper does not adversely impact the appearance of the decorative paper laminate. A decorative paper is also known as a décor paper.
To achieve required abrasion, scuff, and mar resistance, typically, a separate overlay is used as the top layer for paper laminates. An overlay usually comprises the same resin as the one that is used for the resin impregnated decorative paper.
A laminate has been made by applying to the outer layer of a composite structure a mixture of an additive amount of a fluorourethane additive, available from E. I. du Pont de Nemours and Company and a melamine resin slurry. Paper laminates may be produced by both low- and high-pressure lamination processes.
Various methods can be employed to provide paper laminates by low-pressure lamination. For example, a single opening, quick cycle press can be used where one or more resin-saturated paper sheets are laminated to a sheet of plywood typically with a 1A face, particle board, or fiberboard.
In a high-pressure lamination process, a melamine overlay and a melamine resin-impregnated décor paper are usually laminated onto a phenolic sheet, which provides additional mechanical support. For example, a “continuous laminator” can be used where one or more layers of the resin-saturated paper are pressed into a unitary structure as the layers move through continuous laminating equipment between plates, rollers or belts. One or two laminated sheets (continuous web or cut to size) may be pressed onto a particle or fiberboard, etc. and a “glue line” used to bond the laminated sheet to the board. Single or multiple opening presses may also be employed which contain several laminates.
The decor paper in such paper laminates generally comprises a resin-impregnated, cellulose pulp-based sheet, with the pulp being based predominantly on hardwoods such as eucalyptus, sometimes in combination with minor amounts of softwood pulps. Pigments (such as titanium dioxide) and fillers are added in amounts generally up to and including about 45 wt % (based on the total dry weight prior to resin impregnation) to obtain the required opacity. Other additives such as wet-strength, retention, sizing (internal and surface) and fixing agents may also be added as required to achieve the desired end properties of the paper. The resin can be a thermosetting resin selected from the group consisting of a polymer of diallyl phthalate, epoxide, urea formaldehyde, urea-acrylic acid ester copolyester, melamine formaldehyde, melamine phenol formaldehyde, dicyandiamide-formaldehyde, urethane, curable acrylic, unsaturated polyester and phenol formaldehyde and mixtures thereof.
A need exists for such laminates, produced by a low or high pressure lamination process, to impart easy clean characteristics to the decorative surface portion of the laminate to enhance the utility of such laminates in end-use applications such as table and countertops, wall panels and floors.